Process for producing paper bags with handles

ABSTRACT

A process for producing paper bags with handles glued to the insides of the facing opening edges, includes perforating a paper web with transverse perforation lines spaced at distances corresponding to the section lengths necessary to produce the bags. At a given distance from the transverse perforation lines the handles are glued in adjacent pairs to the web in such a way that the outer handle parts project beyond the transverse perforation lines. The web is joined together into a tubular web by folding over its side edges, such that the handles face each other. The overlapping side edges that have been folded together are glued to form a seam. The sections are detached along the transverse perforation lines and each section is provided with a bottom portion at the end opposite the handles. Adhesive coatings are applied to the web in a transverse direction between arms of the handle and Z-shaped folds are made in the adhesive area and folded onto the adhesive, using pressure, to prevent the upper edge of the bag from tearing.

FIELD OF THE INVENTION

The invention relates to a process for producing paper bags with handlesglued to the insides of the facing opening edges, in which a paper webis provided with transverse perforation lines at distances correspondingto the section lengths necessary to produce the bags. At a givendistance from the transverse perforation lines the handles are glued inadjacent pairs to the web in such a way that the outer handle partsproject beyond the transverse perforation lines.

The web is joined together into a tubular web by folding over itslateral edges, such that the handles face each other. The overlappinglateral edges that have been folded together are glued to form a seam.The sections are detached along the transverse perforation lines andeach section is provided with a bottom portion at the end opposite thehandles.

BACKGROUND OF THE INVENTION

The handle bags produced by a known process include opening edges whichare formed by tear lines and handles which extend beyond the edges. Thehandle arms are glued to the inner faces of the bag with reinforcingstrips immediately below the opening edges. The opening edges formed bythe tear lines not only give the bag an unattractive appearance; theyalso tear easily, so that the bag may be destroyed or reduced in itsutility. It is therefore desirable to reinforce the bag by folding overthe opening edges and then gluing the folded over portions together.

SUMMARY OF THE INVENTION

The purpose of the invention, therefore, is to create a process for theproduction of bags having opening edges which are provided with foldedover reinforced portions.

The invention solves this problem by providing a process in which, inthe area in which the handles are glued, the web is provided withadhesive coatings between the handle arms and with Z-shaped folds havingtwo parallel fold lines which lie in the area of the handle arms. Whenthe individual sections are torn from a tubular web that has been foldedand glued according to the invention, the result is a bag workpiecewhose edges are folded inward, with the areas folded on top of eachother being glued together. In forming the Z-folds the arms of thehandles are also folded against each other, so that the handles lie onthe inside of the bag section. When the sections have been provided witha bottom portion, the result is a bag with opening edges that are formedby folded edges, i.e., the opening edges are formed by folding over theedges of the bag workpiece. To use these bags as bags with handles, thebags must first be opened by the user and the handles pulled out.

The inwardly folded handles also provide an advantage in that beforebeing used the carrying bags have a rectangular form, without thehandles projecting beyond the opening edges. As the handles are folded,the opening sides have approximately the same thickness as the bottomareas that are formed by folds, so that a handle bag produced accordingto the invention process can be advantageously stacked into straightstacks having edges which are flush. This is an advantage both forstorage purposes and in keeping the bags ready for use.

The Z-shaped folds can be expediently made by applying the transverseperforation lines to the area of the fold edges which are used to foldthe web side opposite the handles partially onto itself. The Z-shapedfolds will preferably be applied in such a way that the transverseperforation lines lie on the web parts that overlap the center line ofthe folds. This procedure facilitates tearing off the bag workpiecesfrom the tubular web without the folded edge areas being inadvertentlypulled out again.

It is useful to prepare for the folding process by applying pre-creasinglines.

In a further embodiment of the invention, the handle arms are providedwith pre-creasing lines which lie between the adhesive areas and theadjacent pre-creasing lines. In this manner it is assured that theadhesive areas are below the opening edges formed by fold edges, andthis in turn results in reinforcement of the opening edges.

The web may be expediently provided with four stamped holescorresponding roughly to the width of the handle arms and positionedadjacent to the transverse perforation lines. These holes are applied insuch a way that when the handles are pulled out from the carrying bagthe adhesive areas positioned at the edge and formed by the folds do nothave to be torn apart.

Upon or after forming the web tube the web may be expediently providedwith side folds by folding over the side portions. This results in bagswith side gussets, which can be more easily filled than bags providedonly with simple folds.

The sections torn from the web can be provided in a conventional mannerwith block-shaped or cross-shaped bottom portions.

BRIEF DESCRIPTION OF THE DRAWINGS

An exemplary embodiment of the invention will be described in greaterdetail on the basis of the drawings. The drawings show:

FIG. 1 is a schematic plan view of a continuous paper web showingsequential production steps.

FIG. 2 is a further schematic plan view of a continuous paper web,showing further sequential production steps.

FIG. 2a is a cross-sectional view taken along line III--III in FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A paper web which may be a kraft paper web and which is moved in thedirection of the arrow is provided with transverse perforation lines 3at distances representing the section length of a bag workpiece.Elongated holes 2 are punched out along the border of the perforationlines 3. The position of these holes 2 coincides with the arms of thehandles applied in the next processing step. The punched holes 2 areapplied to the side of the transverse perforation lines 3 which laterforms the opening edge of the bags.

In the next processing step the handles 4 are glued on in such a waythat the handle cross-pieces project beyond the perforation lines 3. Thehandles 4 consist of folded multi-layer paper strips, which are foldedin the manner shown to form a U-shaped handle. The ends of the handlearms are provided with reinforcing strips 4' which also serve for gluingthe handle 4 to the flat paper web 1.

In the next processing step adhesive coatings 5 are applied between thehandle arms, in the area of the forward edges of the reinforcing strips4' which serve for gluing the handle.

In the next processing step the web is provided with two parallelpre-creasing lines 6, 7 which lie between the adhesive coatings 5 andthe perforation lines 3 and run below the handle arms, which are notcovered by the pre-creasing line.

The handle arms are also provided with a pre-creasing line which liesbetween the adhesive coatings 5 and the pre-creasing line 6. Thepro-creasing lines 8 which cover only the handle arms are locatedapproximately in the terminal area of the stamped out holes 2.

In the next processing step, the web is folded along the pre-creasinglines 6, 7 into Z-shaped folds, in the manner illustrated in FIGS. 2 and2a, such that the pre-creasing lines 6, 7 form the fold edges. By meansof these folds the web section located between the folding lines 6, 7 isfolded onto the adhesive coatings 5, and the web section adheres to theadhesive coatings with the application of pressure. The transverseperforation lines 3 lie behind the fold edge 7, as can be seen in FIGS.2 and 2a.

With the formation of the Z-fold, the handle arms of the handles 4 arealso folded 180° over themselves and the folding lines are displacedrelative to the fold edges 6.

In the following processing step the lateral portions of the web arefolded over so that the web is brought together to form a tube in whichthe handles precisely overlap with each other. The overlapping edgeareas of the folded over sides are glued together in a conventional way.

The individual bag workpieces are detached from the tubular web thusformed and are provided with bottom portions, to provide bags that areready for use.

What is claimed is:
 1. A process for producing paper bags with handlesglued to the insides of the facing opening edges,comprising providing apaper web with transverse perforation lines at distances correspondingto the length of a section necessary to produce bag, gluing handles tothe web in adjacent pairs at a given distance from the transverseperforation lines, wherein the outer handle parts project beyond thetransverse perforation lines, joining side edges of the web togetherinto a tubular web by folding over the side edges, such that the handlesface each other and the overlapping side edges that have been foldedover are glued together, detaching the sections along the transverseperforation lines, and providing bottom portions at ends of the bagsopposite the handles, said process further comprising: providing the webwith adhesive coatings in a transverse direction between arms of ahandle in the area in which the handles are glued on, and providingZ-shaped folds comprising two parallel fold lines lying in the area ofthe handle arms.
 2. A process according to claim 1, comprising preparingthe Z-shaped folds wherein the transverse perforation lines lie in thearea of the fold edges that are used in partially folding onto itselfthe web side opposite the handles.
 3. A process according to claim 2,comprising preparing the Z-shaped folds wherein the transverseperforation lines lie on web parts overlapping the center line of thefolds.
 4. A process according to claim 1, comprising preparing theZ-shaped folds by applying pre-creasing lines.
 5. A process according toclaim 4, comprising providing the handle arms with pre-creasing lineswhich lie between the adhesive areas and adjacent pre-creasing lines. 6.A process according to claim 1, comprising providing the web adjacentthe transverse perforation lines with four stamped holes having a widthapproximately corresponding to that of the handle arms.
 7. A processaccording to claim 1, further comprising forming side folds in the webfor forming side gussets on the bags.
 8. A process according to claim 7,comprising creasing the side edges before folding the sides and gluingthe sides together to form a tube.
 9. A process according to claim 7,comprising creasing the side edges after folding the sides and gluingthe sides together to form a tube.
 10. A process according to claim 1,wherein the sections torn from the web are provided with block-shapedbottom portions.
 11. A process according to claim 1, wherein thesections torn from the web are provided with block-shaped bottomportions.